A unique, complex variant Philadelphia chromosome translocation in a patient with typical chronic myelogenous leukemia

The Philadelphia (Ph) chromosome [der(22) t(9;22) (q34;q11)] is the charact eristic chromosomal abnormality found in chronic myelogenous leukemia (CML) . This chromosome has been reported in patients with other chromosomal abno rmalities. In this study, we describe a patient with hematologically typica l chronic-phase CML with an unusual and complex translocation involving chr omosomes 9, 11, and 22. These complex translocations were identified by G-b anded conventional cytogenetics and confirmed by fluorescence in situ hybri dization (FISH) using whole chromosome painting probes (wcp). To the best o f our knowledge, these are unique translocations involving the short and th e long arms of chromosome 9 in 4 different translocations with the short ar m of chromosome 11 and the long arm of chromosome 22.